Vascular endothelial growth factor (VEGF) is a signal protein that stimulates vasculogenesis (i.e. de novo formation of new blood vessels) and angiogenesis (i.e. formation of new blood vessels from pre-existing vessels). There are at least six subtypes of VEGF, i.e. VEGF-A, VEGF-B, VEGF-C, VEGF-D, virus VEGF-E and placental VEGF (PIGF). VEGF-A is associated with increases of vascular permeability, degeneration of the extracellular matrix and cell aggravation. Four isomers of VEGF-A that arise from alternative splicing of mRNA have been reported in humans (VEGF121, VEGF165, VEGF184, VEGF206) (Ferrara and Davis Smyth, Endocr Rev, 1997, 18:1-22). VEGF-A binds to receptors VEGFr-1 and VEGFr-2 (Kajdaniuk et al., Endokrynol Pol, 2011, 62(5):444-55; Kajdaniuk et al., Endokrynol Pol, 2011, 62(5):456-64).
The specificity of VEGF action for endothelial cells supports a key role in the process of abnormal blood vessel growth and vascular leakage. Anti-VEGF agents have demonstrated efficacy in reducing corneal neovascularisation in both animal models and clinical trials (Okamoto et al., Am J Pathol, 1997, 151:281-91; Adamis et al., Arch Ophthalmol, 1996, 114:66-71). Specifically, anti-VEGF antibodies have been used for the treatment of treatments of intraocular neovascular disorders.
Currently available anti-VEGF antibodies are bevacizumab and ranibizumab. Bevacizumab is a full-length, humanized murine monoclonal antibody that recognizes all isoforms of VEGF. Ranibizumab is the Fab fragment of the humanized murine monoclonal antibody that is used to create bevacizumab and has been affinity-matured so that it binds VEGF-A with a significantly higher affinity than bevacizumab. Ranibizumab and bevacizumab appear to have similar efficacy profiles in the treatment of neovascular age-related macular degeneration although rare adverse events seem to occur more often with bevacizumab (Johnson and Sharma, Curr Opin Ophthalmol, 2013, 24(3):205-12).
For medical purposes stable antibody compositions are of great interest, in particular ready-to-use solutions which require no dissolution or reconstitution before use. A main problem of such a liquid composition is a decreasing antibody content due to the formation of antibody dimers or insoluble particles during repeated freeze/thaw cycles during manufacturing or antibodies being degraded and forming degradation products during long-term storage.
Many efforts have been made to provide a method for storing antibodies in solutions. Stabilising effects were found by adding polymers including proteins such as human serum albumin or oligomers such as polyols, amino acids, and surfactants as stabilisers for preventing chemical or physical changes. However, the addition of biopolymers such as proteins as stabilisers is inconvenient, as it requires a very complicated step for eliminating contaminants such as viruses and prions.
Moreover, antibody-containing compositions tend to form high-viscosity solutions by molecular interactions. Sugars such as trehalose or sucrose enhance molecular interactions and increase viscosity and the resulting high-viscosity compositions can be difficult to dispense, draw into syringes and inject. Further, the use of a sugar makes a formulation more expensive and the use of sugars which do not naturally occur in mammals may pose a risk for intolerance.
U.S. Pat. No. 8,372,396 B2 describes monoclonal antibody preparations formulated in a saccharide-containing histidine-acetate buffer.
EP 0 661 060 B1 describes stable, highly concentrated intravenously tolerable immunoglobulin preparations.
US 2011/0076273 A1 discloses highly concentrated anti-CD20 antibody formulations comprising a buffering agent, a stabilizer or a mixture of two or more stabilizers, a non-ionic surfactant and optionally a hyaluronidase enzyme.
EP 1 977 763 A1 discloses antibody-containing lyophilized formulations, wherein the formulations substantially consist of an antibody, one or more amino acids, a salt as a buffer, and a surfactant and are free from reducing sugars, non-reducing sugars, sugar alcohols or polysaccharides.
WO 2011/084750 A1 discloses aqueous stable antibody formulations comprising an arginine buffer.
It is an object of the present invention to provide a pharmaceutical composition which is suitable for intravitreal injection and which is stable in liquid form without the addition of excipients such as preservatives or sugars. Preferably such a composition is suitable for the treatment of AMD and formulated in a prefilled syringe. Another object of the present invention is to provide a stable liquid pharmaceutical composition which is formulated such that it does not contain any ingredients which do not naturally occur in humans.